php - ニュースレターの購読解除リンクを生成するには?

Question

PHPでニュースレターを書きたいです。しかし、質問があります。登録解除のコードを生成するにはどうすればよいですか。実際、各加入者に一意のコードが必要です。たとえば、「http://net.tutsplus.com/ 」では、「 http://tutsplus.us1.list-manage.com/profile?u=0154weg635df2fdwied2541cbed&id=c5652sdfre7&e=8758563dfgde 」のようなものを見ることができます。もう 1 つの質問は、このコードをデータベースに保存するか、保存しないかということです (各人に固有のものであれば、ニュースレターを送信するたびに生成する必要はないと思います)。何か案が？

Answer 1

Yes it shoould be saved in a database. You should use something like wamp, lamp or xampp. These are local servers and gives you a mysql database (phpmyadmin) to work in.

to connect with the database, you can use this:

<?php
    define("DB_HOST", "localhost");/*host*/
    define("DB_USERNAME", "username");/*username*/
    define("DB_PASSWORD", "pass123");/*password*/
    define("DB_NAME", "mydatabase");/*database name*/

    try
    {
        $db_conn = new PDO('pgsql:host='.DB_HOST.';dbname='.DB_NAME,DB_USERNAME,DB_PASSWORD);
    }
    catch(PDOException $e)
    {
        print "Error!:".$e->getMessage()."\n";
        die();
    }
?>

then, you can try to create a new table in mysql like this:

CREATE TABLE subcribe
(
subscribeId     INT,
emailadress     VARCHAR(60),
....
);

then, you can add a subscriber to your database like this:

if he logs in, you set a cookie for is emailadress:

setcookie('emailadress',$hisEmailadress,time()+3600);

then add subcriber:

  $emailadress=$_COOKIE['emailadress'];
    $subscriberId = $db_conn->prepare('SELECT MAX(subscriberId) FROM subcribe');
    $subscriberId ->execute();
    $row = $subscriberId ->fetch(PDO::FETCH_BOTH);
    $subscriberId = $row[0]+1;/*unique number because it's one higher then max*/    
    $subscriber = $db_conn->prepare("INSERT INTO subscribe(subscriberId, emailadress) VALUES('$subscriberId','$emailadress')");
    $subscriber ->execute();

to unsubscribe, just do this:

$unsubscribe = $db_conn->prepare('DELETE FROM subscribe WHERE emailadress=:emailadress');
$unsubscribe->bindParam(':emailadress',$_COOKIE['emailadress'],PDO::PARAM_STR);
$unsubscribe->execute();

TO GENERATE A LINK, you can do it like this and send it to the persons emailadres:

$length = rand(5, 10);
$link= "";
for($i=0;$i< $length;$i++)/*create random link*/
{
   $char = rand(0, 256);

   if(($char>=65 && $char<=90) || ($char>=97 && $char<=122) || ($char>=48 && $char<=57))
   {
      $char = chr($char);
      $link.= $link;
   }
   else
    $i--;
}

$hash =  hash("ripemd160",$link);
setcookie('unsubscribe',$hash,time()+300);

$result = mail($emailadress, 'unsubscribe link', 'you are about to unsubscribe yourself. Click this link to unsubscribe: http://yourSite.php?link='.$link);

And in this page, you can use the code to delete the subscriber as mentioned above.

PS: the link itself shouldn't be add to the database because you can set a cookie which is valid for a certain amount of time (here this is 5 minutes). in the page this page you can then add an if-test to see if the cookie was set and then delete the subscriber. if(isset($_COOKIE['unsubscribe'])){...}

Hope it helped ;)